Rotating heat exchanger with flow transmission

ABSTRACT

A rotating heat exchanger, biased with a liquid and a gaseous heat carrier, in which the pump for the liquid heat carrier is combined with the heat exchanger into an integral unit and in which the flow ducts for the liquid between the impeller discs are provided with turbine blading so that pump and turbine represent a torque converter and the liquid heat carrier drives the rotating heat exchanger. The rotating heat exchanger comprises ducts, through which the liquid heat carrier flows and which are disposed near the periphery of the rotor. The motor of the heat exchanger is coupled to a coaxially disposed pump and the hollow impeller disc, subdivided into outwardly and inwardly extending flow ducts, is provided in its interior with turbine blading.

United States Patent Laing 1 Sept. 5, 1972 [54] ROTATING HEAT EXCHANGER WITH Primary ExaminerHenry F. Raduazo FLOW TRANSMISSION Attorney--Pennie, Edmonds, Morton, Taylor and [72] inventor: Nikolaus Laing, Hofener Weg 35- Adams Aldingen near Stuttgart, [57] ABSTRACT A rotating heat exchanger, biased with a liquid and a [22] Flled' Apnl 1970 gaseous heat carrier, in which the pump for the liquid [21] App]. No.: 32,628 heat carrier is combined with the heat exchanger into an integral unit and in which the flow ducts for the liquid between the impeller discs are provided with [30] Forelgn Application Pnonty Dam turbine blading so that pump and turbine represent a April 28, 1969 Austria ..A 4083/69 torque converter and the liquid heat carrier drives the rotating heat exchanger, (g The rotating heat exchanger comprises ducts, through [58] Fe'ld s 165/7 8 9 415/147 which the liquid heat carrier flows and which are I disposed near the periphery of the rotor. The motor of the heat exchanger is coupled to a coaxially disposed [56] References cued pump and the hollow impeller disc, subdivided into UNITED STATES PATEN'IS outwardly and inwardly extending flow ducts, is pro- 2 680 007 6/1954 A b kl 165/86 vided in its interior with turbine blading.

, r uc e v 7 Claims, 5 Drawing Figures PAIENTEDSEP 5 I972 SHEET 1 [IF 3 PATENIEDSEP 5 m2 SHEET 2 OF 3 FIG. 2

PAIENTEDsEP 5 m2 SHEET 3 BF 3 FIG. 4

FIG. 5

ROTATING HEAT EXCHANGER WITH FLOW TRANSMISSION THE PRIOR ART Rotating heat exchangers are heat exchangers in which finned tubes or annular ribs, traversed by tubes, are disposed in the manner of a drum in parallel to a central axis and are are adapted to rotate about such axis. In the zone of the fins, the gaseous heat carrier is delivered radially and outwardly by the action of centrifugal and shear forces. In their simplest form, rotating heat exchangers therefore represent an integration of blower and heat exchanger.

The advantage of such heat exchangers in the first case is due to the much smaller space requirements compared with stationary heat exchangers, on the other hand the noise characteristics are exceptionally favorable compared with the blower noise of force-ventilated stationary heat exchangers. The inertia mass of rotating heat exchangers is subject to an extensive starting delay due to the large accelerating forces, a

feature which disadvantageously precludes the use of normal electric motors. Owing to the large starting torques and speeds which are very low by comparison to conventional blowers, variable speed transmissions would be very complex. Moreover, it is desirable for the exchanged quantities of heat and therefore for the temperatures of the two media to be regulated under optimum conditions of efficiency.

DESCRIPTION OF THE INVENTION This problem is solved according to the invention to providing a pump for the liquid heat carrier and constructing the flow ducts of the heat exchanger whereby they can perform the function of a turbine so that the rotating heat exchanger is constructed as an integrated blower, heat exchanger and flow transmission or fluid torque convertor, charged by the liquid heat carrier. By contrast to transmissions having mechanical power flow means, as for example gear transmissions, flow transmissions are unaffected by high accelerating torques during starting of the prime mover and may moreover be steplessly regulated with simple means. According to the invention, thermal regulation and speed regulation may be performed by restricting the throughput of the pump circuit and by varying the inlet twist. The solution provided by the invention is of particular importance for very large heat exchangers of the type employed for the dissipation of condensation heat in air conditions systems, also in conjunction with evaporation cooling in an open circuit.

The invention will be explained hereinbelow by reference to the following illustrations in which FIG. 1 is a rotating heat exchanger with flow coupling and vortex adjustment in a system with water injection as evaporation cooler.

FIG. 2 shows the zone around the axis of rotation of a rotating heat exchanger with flow transmission and vortex adjustment.

FIG. 3 is a section through the liquid inlet and exit duct along the line III-III of FIG. 2.

FIG. 4 shows in diagrammatic form a section through the hollow impeller disc with heat exchanger tubes and flow transmission.

FIG. 5 is a section through the upper zone of the impeller disc along the line V-V of FIG. 4.

FIG. 1 shows apparatus according to the invention which may be used generally as a heat exchanger with air or in particular as an evaporation cooler. A rotor 8 comprises in part three bulkheads, a bulkhead 1 facing the suction side of air flow passing into the rotor, a bulkhead 2 facing the delivery side of a liquid heat carrier flowing radially outwardly within the rotor and a bulkhead 3 interposed between bulkheads l and 2. It is seen that bulkheads 2 and 3 form a radial outwardly extending annular chamber to contain flow of liquid heat carrier radially outwardly of the rotor and that bulkheads 1 and 3 form a radial inwardly extending annular chamber to contain flow of liquid heat carrier radially inwardly of the rotor. A stationary wall 4 covers the end of the heat exchanger. An inner tube group 5 comprising axially extending flow ducts is connected to the disc-shaped bulkhead bulkhead l and the bulkhead 3. An outer tube group 6 comprising axially extending flow ducts is connected to the bulkhead 3 and communicates with the annular chamber between the bulkheads 2 and 3. On their opposite ends, all tubes are in communication with each other through the annular chamber 7. The tubes of the tube groups 5 and 6 have thereon a plurality of closely spaced radially extending fins 5' and 6' which serve to increase the effective heat exchange area of the tubes The rotor 8 is provided with a tube socket 9 for journalling. A stationary intermediate tube 10 is connected with a suction tube 11 while the annular chamber between the tubes 9 and 10 extends into a discharge tube 12. A motor 13 drives a pump impeller 15 through a shaft 14, said impeller communicating with the cavity between the bulkheads 2 and 3 and being adapted to deliver the liquid heat carrier to the outer tube zone 6. The liquid heat carrier then flows through the annular chamber 7 below the tube ends of the zone 5 and 6, enters through the tubes of the inner zone 5 and then flows into the annular chamber enclosed by the bulkheads 1 and 3 and thereafter flows to the discharge tube 12. Blading is provided on the intermediate bulkhead 3 or on the bulkheads l or 2. The apparatus will then function as a fluid torque coupling.

The arrows 16, 17 and 18 indicate the direction of flow of the gaseous heat carrier which is given a radially outward thrust from the heat exchanger due to the shear forces imparted to the gaseous carrier by the closely spaced radially extending fins 5' and 6';.

FIG. 2 shows another embodiment of the invention in which the motor 20 drives the pump impeller 22 through the shaft 21. In this case too, the motor is subdivided into two annular chambers 23 and 24. The duct 23 is provided with turbine blading so disposed that the liquid heat carrier enters the externally disposed heat exchanger tubes without shock surges. In the lower annular chamber 24 the liquid flows through a second set of turbine blading and then through the stationary diffuser wheel 25. By contrast to the embodiment described with reference to FIG. 1 this embodiment therefore refers to a torque converter comprising a step-down flow transmission. A pivotable diffuser blade 26, which may be operated by a servomotor 27, is disposed in the suction zone, In this embodiment of the invention regulation is obtained by varying the pretwist of the liquid entering the pump 22.

FIG. 3 is a section along the line III-III in which the pivotable diffuser blade may be recognized.

FIG. 4 shows in diagrammatic form a section through the motor 40 of a rotating heat exchanger having the chambers 23 and 24, the inner tube zone 5 and the outer tube zone 6. The elements of the flow transmission system comprise the pump impeller 22, the turbine blading 41 and 42 and the stationary diffuser wheel 25 which is required for torque conversion.

FIG. 5 is a section along the line V-V of FIG. 4 in which the rearwardly curved blading 52 of the pump impeller 22 and the turbine blading 41, which extends almost radially to minimize friction losses in the annular chamber 23 and to reduce surge losses when the liquid heat carrier enters the heat exchanger tubes of the zone 6, appear in sectional form. The tubes of the zone 6 form the blading ducts 53 for delivering the gaseous heat carrier, preceded by the blading ducts in the tube zone 5, not shown. The condition of minimum friction in the annular chamber 24 and optimum flow on to the diffuser wheel blading 25 is provided by the rearwardly curved turbine blading 42, shown in broken lines, having an almost radial entry at the external circumference. To reduce the twist, the diffuser wheel blading, also shown in broken lines, terminates radially, with the exception of the required exaggeration of angle.

I claim:

1. A fluid driven rotatable heat exchanger for exchange of heat between first and second pumpable heat carriers where said heat exchanger comprises a rotor with axially extending flow ducts near the periphery thereof through which the first fluid heat carrier is adapted to flow, a plurality of closely spaced radially extending fins on said axial flow ducts for increasing the effective heat exchange area of the rotor and for accelerating the second fluid heat carrier with a radially outward velocity component due to shear forces being imparted on the second heat carrier by the fins when the rotor is rotated, a motor, inlet and outlet tubes through which the first heat carrier is adapted to enter and leave said heat exchanger, and means connecting said ducts with the middle of said rotor and means comprising elements which seal the rotor with respect to the outlet tube; a rotatable pump impeller connected to said motor and coaxially disposed within said rotor where said impeller receives said first fluid heat carrier from said inlet tube, means dividing said rotor into radial outwardly and inwardly extending annular chambers through which said first fluid heat carrier flows, said radial outwardly extending chamber having turbine blades therein whereby the first fluid heat carrier flowing between said pump impeller and said radially outwardly extending chamber forms a fluid coupling therebetween whereby the motor is operably connected to said rotor to rotate the same.

2. A fluid driven rotatable heat exchanger according to claim 1 further characterized in that said turbine blades extend in a substantially radial direction.

3. A fluid driven rotatable heat exchanger according to claim 2 characterized in that the radial inwardly extending chamber has blading therein curved against the direction of rotation.

4. A fluid driven rotatable heat exchanger according to claim 2 characterized in having a stationary diffuser wheel disposed within the radial inwardly extending chamber.

5. A fluid driven rotatable heat exchanger according to claim 1 having in addition a tube socket connected to the rotor and a journal means for rotatably supporting said tube socket.

6. A fluid driven rotatable heat exchanger according to claim 1 having means for varying the speed of the motor whereby the flow of heat carrier through said exchanger is varied to regulate the speed of rotation of said rotor.

7. A fluid driven rotatable heat exchanger according to claim 6 having pivotable blade means for varying the pretwist of said first heat carrier as it contacts said pump impeller whereby the speed of rotation of said rotor is varied.

' 23x3 UNI TED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,688,836 Q Q Dated September 5, .1972

Inventor(s) I LAING .1 i

It is certified that error appears- 1111mm Behave-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, line 8, delete "are" first occurrence; 8

Col". -1, line L2, after "tran smi ssionsq insert -or fluid I torque convertor--;

C01. 2, line 173 after "bulkhead" first vc 'xicurrence, insert 1 and communicates with the annular chamber between said- Col. 2, line I 51, change "motor" to --rotor Col. 3, line 2, change "motor" to -i-rotor--'-.

Signed and sealed this 17th day of April 1973.

(SEAL) Attest:

EDWARD IM.FLETCHER,JR. ROBERT'GOTTSCHALK' I Attesting Officer Commissioner of Patents 

1. A fluid driven rotatable heat exchanger for exchange of heat between first and second pumpable heat carriers where said heat exchanger comprises a rotor with axially extending flow ducts near the periphery thereof through which the first fluid heat carrier is adapted to flow, a plurality of closely spaced radially extending fins on said axial flow ducts for increasing the effective heat exchange area of the rotor and for accelerating the second fluid heat carrier with a radially outward velocity component due to shear forces being imparted on the second heat carrier by the fins when the rotor is rotated, a motor, inlet and outlet tubes through which the first heat carrier is adapted to enter and leave said heat exchanger, and means connecting said ducts with the middle of said rotor and means comprising elements which seal the rotor with respect to the outlet tube; a rotatable pump impeller connected to said motor and coaxially disposed within said rotor where said impeller receives said first fluid heat carrier from said inlet tube, means dividing said rotor into radial outwardly and inwardly extending annular chambers through which said first fluid heat carrier flows, said radial outwardly extending chamber having turbine blades therein whereby the first fluid heat carrier flowing between said pump impeller and said radially outwardly extending chamber forms a fluid coupling therebetween whereby the motor is operably connected to said rotor to rotate the same.
 2. A fluid driven rotatable heat exchanger according to claim 1 further characterized in that said turbine blades extend in a substantially radial direction.
 3. A fluid driven rotatable heat exchanger according to claim 2 characterized in that the radial inwardly extending chamber has blading therein curved against the direction of rotation.
 4. A fluid driven rotatable heat exchanger according to claim 2 characterized in having a stationary diffuser wheel disposed within the radial inwardly extending chamber.
 5. A fluid driven rotatable heat exchanger according to claim 1 having in addition a tube socket connected to the rotor and a journal means for rotatably supporting said tube socket.
 6. A fluid driven rotatable heat exchanger according to claim 1 having means for varying the speed of the motor whereby the flow of heat carrier through said exchanger is varied to regulate the speed of rotation of said rotor.
 7. A fluid driven rotatable heat exchanger according to claim 6 having pivotable blade means for varying the pretwist of said first heat carrier as it contacts said pump impeller whereby the speed of rotation of said rotor is varied. 